This invention relates in general to systems that limit and/or otherwise control the speed of a vehicle in accordance with a desired maximum speed. In particular, this invention relates to an improved structure for such a vehicle speed limiting and/or controlling system that is responsive to signals generated from a global positioning satellite (GPS) system for determining a desired maximum speed and that affirmatively limits and/or otherwise controls the speed of the vehicle in accordance with that predetermined maximum speed.
Many modern vehicles are provided with one or more active safety and driver assist systems to improve safety and enhance the driving experience. One important focus of these systems is the speed at which a vehicle is operated. For example, the speed at which an inexperienced driver operates a vehicle may be of particular concern to the parent of the driver or the owner of the vehicle.
In one known active safety system of this general type, the actual speed of the vehicle is limited (i.e., prevented from exceeding) and/or otherwise controlled (i.e., affirmatively guided toward another speed) in accordance with a single predetermined maximum speed. This single predetermined maximum speed may be either permanently engaged by the manufacturer of the vehicle at a factory-preset magnitude or selectively engaged by the parent of the driver or the owner of the vehicle by means a programmable controller, such as is currently available under the Ford® MyKey® programmable speed limiting system. In either event, the single predetermined maximum speed is initially set at a desired magnitude. Thereafter, when the vehicle is operated at this predetermined maximum speed (or at a threshold speed that is a predetermined differential from the predetermined maximum speed), an alarm is generated to alert the driver. Additionally (or alternatively), an electronic controller provided in the vehicle is actuated to affirmatively limit and/or otherwise control the speed of the vehicle relative to the predetermined maximum speed.
Although these types of speed limiting and/or controlling systems are effective, it is known that the maximum safe speed at which a vehicle can be operated can vary in accordance with the location where the vehicle is being operated. For example, the maximum safe speed at which a vehicle can be operated on an expressway is much higher than the maximum safe speed the same vehicle can be operated on a neighborhood street. To address these differing operating environments, it is known to provide the vehicle with a speed limit sign recognition system. Such as system includes a vehicle-mounted camera that captures an image of a conventional speed limit sign posted on the side of a road. The captured image is fed to an image processor that generates a signal that is representative of the posted speed limit displayed on the speed limit sign. This posted speed limit signal is used to either generate an alarm to alert the driver or affirmatively limit and/or otherwise control the speed of the vehicle relative to the predetermined maximum speed (or both) in the manner described above. Unfortunately, these types of camera-based speed limit sign recognition systems are relatively complex and costly.
Unrelated to the above-described vehicle speed limiting and/or controlling systems, many vehicles are provided with a conventional global positioning satellite (GPS) navigation device. These well known GPS navigation devices (which may either be provided as an integral part of the vehicle or as a portable aftermarket unit) are programmed to display both the current location of the vehicle on a displayed map and the actual speed of the vehicle at that particular location. Additionally, some of these GPS navigation devices are further programmed to both display the posted speed limit at the current location of the vehicle and generate an alarm if the actual speed of the vehicle exceeds the posted speed limit at that location. However, conventional GPS navigation devices do not affirmatively limit and/or otherwise control the speed of the vehicle.
Thus, it would be desirable to provide an improved structure for a vehicle speed limiting and/or controlling system addresses the issues discussed above.